As we announced at BlizzCon, we're excited about the opportunity to extend our Flexible Raid tech to address some of the long-standing problems we've been grappling with as a design team for over 5 years now. Here's a quick breakdown of how the new system works: We're relabeling Flexible Raid mode Normal, and it will serve as the new baseline point of entry to organized raiding. We're also combining the current 10-player and 25-player Normal modes into a single Heroic difficulty. Finally, we're consolidating 10-player and 25-player Heroic into a new fixed-size 20-player Mythic difficulty.

This system will allow the vast majority of players to raid with a wide variety of possible raid sizes, and reap the benefits of that structure. One of the major upsides of a 13-player raid is that you don't have to worry about canceling if one or two people aren't able to make it; you also don't have to worry about asking someone to sit out if everyone shows up. This, in turn, means that raiding in an organized group is possible without the same feeling of obligation, and that such groups will be much more resilient in practice.

While we've made significant strides in tuning 10-player and 25-player Normal modes to be comparable in difficulty over the course of Mists of Pandaria (Mists), precise 10 vs. 25 Heroic tuning has continued to be a major challenge, especially on important fights such as Lei Shen (easier with 10) and Garrosh (easier with 25). Consolidating to a single raid size for Mythic will allow us to focus on delivering the best possible experience for our competitive hardcore raiders, while the flexible nature of Normal and Heroic mode provides an avenue for smaller groups to organically grow and continue raiding if they want to give Mythic a try.

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In Warlords, each raid difficulty will have its own weekly lockout. We gave careful consideration to how the lockout system should work, and which difficulties (if any) would share lockouts. Having seen how Flex works today, it's clear there are many benefits to having our raid difficulties on separate lockouts: Players might currently raid Normal or Heroic Siege of Orgrimmar with their guilds on a set schedule, but then join real-life friends on another server for weekend Flex runs and a chance to grab some off-spec loot. Players who are regularly clearing Normal, let alone Heroic, Siege of Orgrimmar quickly find that they don't need much main-spec loot from Flex. Most players who are doing Siege in multiple difficulties each week are doing so with different social groups, and we'd like to preserve players' freedom to do so.

As for Heroic and Mythic, having those difficulties share a lockout would present a number of technical as well as logistical challenges: Heroic is a flexible-size loot-based lockout; Mythic is a fixed-size boss-based lockout, limited to a single realm, with a static ID. The two simply aren't congruent. Having these on a separate lockout also simplifies some things for high-end guilds that are trying to manage progress on a limited schedule, and currently have to carefully budget enough time at the end of each week to re-kill remaining bosses on Normal difficulty for loot. In Warlords, those groups will be able to frontload their farming for the week and then work on Mythic progression for the rest of the week without worry.

Reflecting on the (Trial of the Crusader problem) in Patch 3.2, much of the issue there stemmed from the way Emblems worked at the time. Badges obtained from raid bosses and dungeons were necessary just to buy set pieces, and so guilds felt obligated to keep clearing something like 10-player Normal Trial of the Crusader, even if they needed none of the loot, just for the extra Emblems. In Warlords, we are scaling back Valor, along with the incentive to cap Valor weekly. Less linear layouts and shortcuts that allow experienced groups to skip to certain bosses should let raiders target the specific content that interests them. In general, we're erring on the side of giving players choice and freedom, and we feel that our character progression systems are better structured now and will not encourage excessive repetition of the same content.